Method for the immunological determination of an analyte

Abstract

The invention concerns a method for the immunological determination of an analyte in a sample using magnetic particles coated with the analyte to be determined or analyte-specific bonding partners and directly detectable non-magnetic particles coated with analyte-specific bonding partners or the analyte to be determined or using a non-magnetic substance which is indirectly detectable, and incubation of the reaction mixture. The method is characterized in that the magnetic particles are subsequently separated from the reaction mixture using a magnetic test strip and the analyte concentration is determined directly.

What is claimed is:  
     
       1. A procedure for the immunological determination of an analyte in a sample comprising 
       a) incubating a sample which may comprise said analyte with  
       i) magnetic particles coated with a) the analyte to be determined or b) a first analyte-specific binding components and either  
       ii) directly or indirectly detectable non-magnetic particles coated with a) a second analyte-specific binding component or b) the analyte to be determined, or  
       iii) an indirectly detectable non-magnetic substance coupled to said second analyte-specific binding component;  
       b) allowing said analyte and said coated magnetic particles and either said coated non-magnetic particles or said coupled non-magnetic substance to interact;  
       c) removing said magnetic particles and materials attached thereto by inserting and removing a magnetic test strip; and  
       d) determining the analyte concentration directly on said removed magnetic test strip.  
     
     
       2. A procedure for the imunological determination of an analyte in a sample comprising 
       a) incubating a sample which may comprise said analyte with  
       i) magnetic particles coated with a) the analyte to be determined or b) a first analyte-specific binding components and either  
       ii) directly or indirectly detectable non-magnetic particles coated with a) a second analyte-specific binding component or b) the analyte to be determined, or  
       iii) an indirectly detectable non-magnetic substance coupled to said second analyte-specific binding component;  
       b) allowing said analyte and said coated magnetic particles and either said coated non-magnetic particles or said coupled non-magnetic substance to interact;  
       c) removing said magnetic particles and materials attached thereto by inserting and removing a magnetic test strip; and  
       d) determining the analyte concentration indirectly by development of a color reaction or electrochemically on said removed test strip.  
     
     
       3. The method according to  claim 1 , wherein said two analyte-specific binding components are antibodies. 
     
     
       4. The method according to  claim 3 , wherein said two antibodies are monoclonal antibodies which are specific for different epitopes of said analyte. 
     
     
       5. The method according to  claim 1 , wherein said non-magnetic substance is an enzyme. 
     
     
       6. The method according to  claim 1 , wherein the magnetic test strip is a flat permanent magnet. 
     
     
       7. The method according to  claim 1 , wherein the magnetic test strip can be washed and reused a plurality of times. 
     
     
       8. The method according to  claim 1 , wherein said particles have a size of 30 nm to 800 μm. 
     
     
       9. The method according to  claim 1 , wherein said particles are of iron, nickel, cobalt, manganese, a lanthanide, a magnetic alloy, an oxide, a composite material, or an organic polymer. 
     
     
       10. The method according to  claim 9 , wherein said lanthanide is neodymium or erbium, said magnetic alloy is an aluminum, nickel, cobalt or copper alloy, said oxide is Fe 3 O 4 , CrO 2 , CoO, NiO 2  or Mn 2 O 3 , said composite material is a ferrite, or said organic polymer is a polystyrene. 
     
     
       11. A procedure for the immunological determination of an analyte in a sample, comprising 
       a) incubating a sample which may comprise said analyte with  
       (i) magnetic particles coated with a first analyte-specific binding component and  
       (ii) non-magnetic particles, optionally having a color different from said magnetic particles, coated with a second analyte-specific binding component,  
       wherein said coated non-magnetic particles are directly or indirectly detectable;  
       b) allowing said analyte and said coated magnetic particles and said coated non-magnetic particles to interact;  
       c) removing said magnetic particles and materials attached thereto by inserting and removing a magnetic test strip; and  
       d) determining the analyte concentration.  
     
     
       12. The method according to  claim 11 , wherein said first and second analyte-specific binding components are monoclonal antibodies. 
     
     
       13. A procedure for the immunological determination of an analyte in a sample comprising magnetic particles coated with an analyte-specific component, to which the analyte and directly or indirectly detectable non-magnetic materials are attached, comprising removing said magnetic particles and said directly or indirectly detectable materials attached thereto from said sample by inserting a magnetic test strip into the sample and removing it, and determining the analyte concentration directly on said removed test strip. 
     
     
       14. The method according to  claim 13 , wherein said analyte-specific binding component is a monoclonal antibody. 
     
     
       15. A procedure for the immunological determination of an analyte in a sample comprising 
       a) incubating a sample which may comprise said analyte with  
       (i) magnetic particles coated with said analyte or with a first analyte-specific component; and  
       (ii) non-magnetic particles, optionally having a different color from said magnetic particles, coated with a second analyte-specific binding component or with said analyte;  
       b) allowing said analyte and said coated magnetic particles and said coated non-magnetic particles to interact;  
       c) removing said magnetic particles and materials attached thereto by inserting and removing a magnetic test strip; and  
       d) determining the analyte concentration directly on said removed magnetic test strip.  
     
     
       16. The method according to  claim 15 , wherein said analyte-specific binding components are monoclonal antibodies. 
     
     
       17. A procedure for the immunological determination of an analyte in a sample, comprising 
       a) incubating a sample which may comprise said analyte with  
       (i) magnetic particles coated with a first analyte-specific binding component and  
       (ii) an indirectly detectable non-magnetic substance, coupled to a second analyte-specific binding component,  
       b) allowing said analyte and said coated magnetic particle and said non-magnetic substance to interact;  
       c) removing said magnetic particles and materials attached thereto by inserting and removing a magnetic test strip; and  
       d) determining the analyte concentration directly on said removed magnetic test strip.  
     
     
       18. The method according to  claim 17 , wherein said analyte-specific binding components are monoclonal antibodies.